May 15, 2009

As the Canadian Army moves to implement its Command Centric operational philosophy, the efficient wireless movement of data on the battlefield will be a critical component of future communications systems. One of the key technologies that Canada will use to provide this capability will be the Enhanced Position Location Reporting System (EPLRS), a battle tested system produced by Raytheon that is constantly undergoing product improvement to meet the evolving needs of the warfighter.

Originally conceived in the 1970s as system to provide U.S. ground forces with a secure anti-jam position location and reporting system, the Position Location Reporting System (PLRS) used a ‘time of flight’ calculation from various radios in the system to provide a location for the units, which was then transferred across the battlefield as data messages. Although the position location function was ultimately taken over by the Global Position System, the data transmission function was enhanced in 1987 to provide a data backbone to support the U.S. military’s digitization efforts.

As concepts of Network Centric Warfare are refined in the land environment, through efforts such as Task Force XXI experimentation, EPLRS has evolved to support the growing need for data transmission on the battlefield for situation awareness and Command and Control functions.

This enhanced system (pronounced “e-plurs”) provides secure tactical wireless communications. Comprised of many radios and one or more network managers, the system provides multiple concurrent communication channels supporting accurate and timely computer to computer communications in a mobile environment. In widespread use by all four branches of the United States military, EPLRS is currently being fielded by the Canadian Army.

A battle-proven robust, high-speed communications system for warfighters on the move, EPLRS provides enhanced Command, Control, and Communications (C3) capabilities by supporting Battle Functional Area, Engagement Operations, and Tactical Internet requirements for battlefield data distribution, position location, navigation, reporting and friendly identification.

Through its contention-free mobile networking architecture, EPLRS provides the warfighter with the capability to seamlessly enter and leave the network while the network automatically reconfigures to overcome line-of-sight limitations.

The U.S. Air Force also uses the system in an air-to-ground and air-to-air configuration to provide its F-16 fighters and A-10 ground support aircraft with a Situational Awareness Data Link capability analogous to LINK 16 for close air support and air intercept tasks.

The latest version of the radio, known as the EPLRS-XF (RT-1915), provides soldiers with a communications system that is interoperable with Internet protocol-based technology and has extended radio-frequency range, among other next-generation capabilities. The expanded frequency version offers 100% interoperability with the existing fleet of EPLRS (RT-1720) radios. EPLRS-XF radios will serve as the mobile backbone for the Canadian Army’s evolving Tactical Internet in land platforms such as the Light Armoured Vehicle and Leopard II tank, and air platforms such as the Griffon helicopter.

“The EPLRS-XF radio gives the war fighter high-speed, on-the-move video and data exchange capabilities for a broad range of applications,” says Jerry Powlen, vice president of Raytheon Network Centric Systems Integrated Communication Systems. “Raytheon continues to evolve our networked communications capabilities to deliver the most advanced solutions to our customers.”

Some of Raytheon’s efforts have focused on the development of a family of EPLRS equipment that can provide the same functionality to a dismounted war­fighter as to a platform such as a LAV or helicopter. Presently, the waveform functionality is available in the RT-1912 and microlight soldier-wearable format. The microlight has been mandated for use in both the U.S. and Australian Army’s soldier modernization efforts. A handheld version of the equipment (DH500), with built-in VOIP capability, is undergoing trials with various armies, including Canada’s.

Other efforts have focused on how EPLRS can be more efficiently used as a wireless communications system. The Canadian Army has been conducting trials in Suffield to evaluate the use of DH500 EPLRS mounted in Aerostats to extend the range and coverage of the network. Design work has also been done for mounting the radios in UAVs. In addition, Canada and the U.S. Marine Corps have been holding trials to evaluate the openness of the EPLRS waveform with respect to integration with commercial applications over IP.

In support of the evolving “Everything over IP” (EoIP), Raytheon has been working on modifying the EPLRS waveform to improve its Mobile Ad-Hoc Networking (MANET) capabilities. Now in testing, the new version includes MANET functionality to simplify network setup and reconfiguration, and reduce management traffic bandwidth overhead.

Raytheon is in the process of executing technical transfer efforts to ensure that Raytheon Canada Limited Support Services (RCSS) in Calgary, which presently supports the microlight EPLRS for the Canadian Army, will be able to support the full range of EPLRS equipment that Canada deploys in the future.
Kim Grant PEng, a former Canadian Army communications officer, currently works for Raytheon Canada (RCSS) as the Director of Technology. Call him at 1-403-295-6906 or by email
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